Can someone help me on my postfix config my main problem is sending from lan it can't send but... i can received when i am testing from yahoo or hotmail going to my postfix mail.
Hoping you guys could help me. Thanks Guys.

Here is my config.

# Global Postfix configuration file. This file lists only a subset
# of all 300+ parameters. See the sample-xxx.cf files for a full list.
#
# The general format is lines with parameter = value pairs. Lines
# that begin with whitespace continue the previous line. A value can
# contain references to other $names or ${name}s.
#
# NOTE - CHANGE NO MORE THAN 2-3 PARAMETERS AT A TIME, AND TEST IF
# POSTFIX STILL WORKS AFTER EVERY CHANGE.

# LOCAL PATHNAME INFORMATION
#
# The queue_directory specifies the location of the Postfix queue.
# This is also the root directory of Postfix daemons that run chrooted.
# See the files in examples/chroot-setup for setting up Postfix chroot
# environments on different UNIX systems.
#
queue_directory = /var/spool/postfix

# The daemon_directory parameter specifies the location of all Postfix
# daemon programs (i.e. programs listed in the master.cf file). This
# directory must be owned by root.
#
daemon_directory = /usr/libexec/postfix

# QUEUE AND PROCESS OWNERSHIP
#
# The mail_owner parameter specifies the owner of the Postfix queue
# and of most Postfix daemon processes. Specify the name of a user
# account THAT DOES NOT SHARE ITS USER OR GROUP ID WITH OTHER ACCOUNTS
# AND THAT OWNS NO OTHER FILES OR PROCESSES ON THE SYSTEM. In
# particular, don't specify nobody or daemon. PLEASE USE A DEDICATED
# USER.
#
mail_owner = postfix

# The default_privs parameter specifies the default rights used by
# the local delivery agent for delivery to external file or command.
# These rights are used in the absence of a recipient user context.
# DO NOT SPECIFY A PRIVILEGED USER OR THE POSTFIX OWNER.
#
#default_privs = nobody

# INTERNET HOST AND DOMAIN NAMES
#
# The myhostname parameter specifies the internet hostname of this
# mail system. The default is to use the fully-qualified domain name
# from gethostname(). $myhostname is used as a default value for many
# other configuration parameters.
#
#myhostname = host.domain.tld
#myhostname = virtual.domain.tld
myhostname = smtp-sm-advantage.smtp-sm-advantage.com
myhostname = smtp-sm-advantage.com

# The mydomain parameter specifies the local internet domain name.
# The default is to use $myhostname minus the first component.
# $mydomain is used as a default value for many other configuration
# parameters.
#
#mydomain = domain.tld
mydomain = smtp-sm-advantage.com

# SENDING MAIL
#
# The myorigin parameter specifies the domain that locally-posted
# mail appears to come from. The default is to append $myhostname,
# which is fine for small sites. If you run a domain with multiple
# machines, you should (1) change this to $mydomain and (2) set up
# a domain-wide alias database that aliases each user to
# user@that.users.mailhost.
#
# For the sake of consistency between sender and recipient addresses,
# myorigin also specifies the default domain name that is appended
# to recipient addresses that have no @domain part.
#
# myorigin = $myhostname,$localhost,$smtp-sm-advantage.com, mci.sm-advantage.com
# myorigin = $mydomain,$smtp-sm-advantage.com,$mci.sm-advantage.com,localhost
myorigin = $mydomain, smtp-sm-advantage, smtp-sm-advantage.com

# RECEIVING MAIL

# The inet_interfaces parameter specifies the network interface
# addresses that this mail system receives mail on. By default,
# the software claims all active interfaces on the machine. The
# parameter also controls delivery of mail to user@[ip.address].
#
# See also the proxy_interfaces parameter, for network addresses that
# are forwarded to us via a proxy or network address translator.
#
# Note: you need to stop/start Postfix when this parameter changes.
#
inet_interfaces = all
#inet_interfaces = $myhostname
inet_interfaces = $myhostname, localhost
#inet_interfaces = localhost

# The proxy_interfaces parameter specifies the network interface
# addresses that this mail system receives mail on by way of a
# proxy or network address translation unit. This setting extends
# the address list specified with the inet_interfaces parameter.
#
# You must specify your proxy/NAT addresses when your system is a
# backup MX host for other domains, otherwise mail delivery loops
# will happen when the primary MX host is down.
#
#proxy_interfaces =
#proxy_interfaces = 1.2.3.4

# The mydestination parameter specifies the list of domains that this
# machine considers itself the final destination for.
#
# These domains are routed to the delivery agent specified with the
# local_transport parameter setting. By default, that is the UNIX
# compatible delivery agent that lookups all recipients in /etc/passwd
# and /etc/aliases or their equivalent.
#
# The default is $myhostname + localhost.$mydomain. On a mail domain
# gateway, you should also include $mydomain.
#
# Do not specify the names of virtual domains - those domains are
# specified elsewhere (see sample-virtual.cf).
#
# Do not specify the names of domains that this machine is backup MX
# host for. Specify those names via the relay_domains settings for
# the SMTP server, or use permit_mx_backup if you are lazy (see
# sample-smtpd.cf).
#
# The local machine is always the final destination for mail addressed
# to user@[the.net.work.address] of an interface that the mail system
# receives mail on (see the inet_interfaces parameter).
#
# Specify a list of host or domain names, /file/name or type:table
# patterns, separated by commas and/or whitespace. A /file/name
# pattern is replaced by its contents; a type:table is matched when
# a name matches a lookup key (the right-hand side is ignored).
# Continue long lines by starting the next line with whitespace.
#
# DO NOT LIST RELAY DESTINATIONS IN MYDESTINATION.
# SPECIFY RELAY DESTINATIONS IN RELAY_DOMAINS.
#
# See also below, section "REJECTING MAIL FOR UNKNOWN LOCAL USERS".
#

# REJECTING MAIL FOR UNKNOWN LOCAL USERS
#
# The local_recipient_maps parameter specifies optional lookup tables
# with all names or addresses of users that are local with respect
# to $mydestination and $inet_interfaces.
#
# If this parameter is defined, then the SMTP server will reject
# mail for unknown local users. This parameter is defined by default.
#
# To turn off local recipient checking in the SMTP server, specify
# local_recipient_maps = (i.e. empty).
#
# The default setting assumes that you use the default Postfix local
# delivery agent for local delivery. You need to update the
# local_recipient_maps setting if:
#
# - You define $mydestination domain recipients in files other than
# /etc/passwd, /etc/aliases, or the $virtual_alias_maps files.
# For example, you define $mydestination domain recipients in
# the $virtual_mailbox_maps files.
#
# - You redefine the local delivery agent in master.cf.
#
# - You redefine the "local_transport" setting in main.cf.
#
# - You use the "luser_relay", "mailbox_transport", or "fallback_transport"
# feature of the Postfix local delivery agent (see sample-local.cf).
#
# Details are described in the LOCAL_RECIPIENT_README file.
#
# Beware: if the Postfix SMTP server runs chrooted, you probably have
# to access the passwd file via the proxymap service, in order to
# overcome chroot restrictions. The alternative, having a copy of
# the system passwd file in the chroot jail is just not practical.
#
# The right-hand side of the lookup tables is conveniently ignored.
# In the left-hand side, specify a bare username, an @domain.tld
# wild-card, or specify a user@domain.tld address.
#
#local_recipient_maps = unix:passwd.byname $alias_maps
#local_recipient_maps = proxy:unix:passwd.byname $alias_maps
local_recipient_maps =

# The unknown_local_recipient_reject_code specifies the SMTP server
# response code when a recipient domain matches $mydestination or
# $inet_interfaces, while $local_recipient_maps is non-empty and the
# recipient address or address local-part is not found.
#
# The default setting is 550 (reject mail) but it is safer to start
# with 450 (try again later) until you are certain that your
# local_recipient_maps settings are OK.
#
unknown_local_recipient_reject_code = 550
# unknown_local_recipient_reject_code = 450
# unknown_local_recipient_reject_code = 554

# TRUST AND RELAY CONTROL

# The mynetworks parameter specifies the list of "trusted" SMTP
# clients that have more privileges than "strangers".
#
# In particular, "trusted" SMTP clients are allowed to relay mail
# through Postfix. See the smtpd_recipient_restrictions parameter
# in file sample-smtpd.cf.
#
# You can specify the list of "trusted" network addresses by hand
# or you can let Postfix do it for you (which is the default).
#
# By default (mynetworks_style = subnet), Postfix "trusts" SMTP
# clients in the same IP subnetworks as the local machine.
# On Linux, this does works correctly only with interfaces specified
# with the "ifconfig" command.
#
# Specify "mynetworks_style = class" when Postfix should "trust" SMTP
# clients in the same IP class A/B/C networks as the local machine.
# Don't do this with a dialup site - it would cause Postfix to "trust"
# your entire provider's network. Instead, specify an explicit
# mynetworks list by hand, as described below.
#
# Specify "mynetworks_style = host" when Postfix should "trust"
# only the local machine.
#
# mynetworks_style = class
# mynetworks_style = subnet
# mynetworks_style = host

# Alternatively, you can specify the mynetworks list by hand, in
# which case Postfix ignores the mynetworks_style setting.
#
# Specify an explicit list of network/netmask patterns, where the
# mask specifies the number of bits in the network part of a host
# address.
#
# You can also specify the absolute pathname of a pattern file instead
# of listing the patterns here. Specify type:table for table-based lookups
# (the value on the table right-hand side is not used).
#

# The relay_domains parameter restricts what destinations this system will
# relay mail to. See the smtpd_recipient_restrictions restriction in the
# file sample-smtpd.cf for detailed information.
#
# By default, Postfix relays mail
# - from "trusted" clients (IP address matches $mynetworks) to any destination,
# - from "untrusted" clients to destinations that match $relay_domains or
# subdomains thereof, except addresses with sender-specified routing.
# The default relay_domains value is $mydestination.
#
# In addition to the above, the Postfix SMTP server by default accepts mail
# that Postfix is final destination for:
# - destinations that match $inet_interfaces,
# - destinations that match $mydestination
# - destinations that match $virtual_alias_domains,
# - destinations that match $virtual_mailbox_domains.
# These destinations do not need to be listed in $relay_domains.
#
# Specify a list of hosts or domains, /file/name patterns or type:name
# lookup tables, separated by commas and/or whitespace. Continue
# long lines by starting the next line with whitespace. A file name
# is replaced by its contents; a type:name table is matched when a
# (parent) domain appears as lookup key.
#
# NOTE: Postfix will not automatically forward mail for domains that
# list this system as their primary or backup MX host. See the
# permit_mx_backup restriction in the file sample-smtpd.cf.
#
# relay_domains = $mydestination
# relay_domains = $smtp-sm-advantage.com,$localhost.localdomain,$localhost

# INTERNET OR INTRANET

# The relayhost parameter specifies the default host to send mail to
# when no entry is matched in the optional transport(5) table. When
# no relayhost is given, mail is routed directly to the destination.
#
# On an intranet, specify the organizational domain name. If your
# internal DNS uses no MX records, specify the name of the intranet
# gateway host instead.
#
# In the case of SMTP, specify a domain, host, host:port, [host]:port,
# [address] or [address]:port; the form [host] turns off MX lookups.
#
# If you're connected via UUCP, see also the default_transport parameter.
#
#relyahost = smtp-sm-advantage.com
#relayhost = $mydomain
#relayhost = gateway.my.domain
#relayhost = uucphost
#relayhost = [an.ip.add.ress]

# REJECTING UNKNOWN RELAY USERS
#
# The relay_recipient_maps parameter specifies optional lookup tables
# with all addresses in the domains that match $relay_domains.
#
# If this parameter is defined, then the SMTP server will reject
# mail for unknown relay users. This feature is off by default.
#
# The right-hand side of the lookup tables is conveniently ignored.
# In the left-hand side, specify an @domain.tld wild-card, or specify
# a user@domain.tld address.
#
#relay_recipient_maps = hash:/etc/postfix/relay_recipients

# INPUT RATE CONTROL
#
# The in_flow_delay configuration parameter implements mail input
# flow control. This feature is turned on by default, although it
# still needs further development (it's disabled on SCO UNIX due
# to an SCO bug).
#
# A Postfix process will pause for $in_flow_delay seconds before
# accepting a new message, when the message arrival rate exceeds the
# message delivery rate. With the default 100 SMTP server process
# limit, this limits the mail inflow to 100 messages a second more
# than the number of messages delivered per second.
#
# Specify 0 to disable the feature. Valid delays are 0..10.
#
#in_flow_delay = 1s

# ADDRESS REWRITING
#
# Insert text from sample-rewrite.cf if you need to do address
# masquerading.
#
# Insert text from sample-canonical.cf if you need to do address
# rewriting, or if you need username->Firstname.Lastname mapping.

# ALIAS DATABASE
#
# The alias_maps parameter specifies the list of alias databases used
# by the local delivery agent. The default list is system dependent.
#
# On systems with NIS, the default is to search the local alias
# database, then the NIS alias database. See aliases(5) for syntax
# details.
#
# If you change the alias database, run "postalias /etc/aliases" (or
# wherever your system stores the mail alias file), or simply run
# "newaliases" to build the necessary DBM or DB file.
#
# It will take a minute or so before changes become visible. Use
# "postfix reload" to eliminate the delay.
#
#alias_maps = dbm:/etc/aliases
alias_maps = hash:/etc/postfix/aliases
#alias_maps = hash:/etc/aliases, nis:mail.aliases
#alias_maps = netinfo:/aliases

# The alias_database parameter specifies the alias database(s) that
# are built with "newaliases" or "sendmail -bi". This is a separate
# configuration parameter, because alias_maps (see above) may specify
# tables that are not necessarily all under control by Postfix.
#
#alias_database = dbm:/etc/aliases
#alias_database = dbm:/etc/mail/aliases
alias_database = hash:/etc/aliases
#alias_database = hash:/etc/aliases, hash:/opt/majordomo/aliases

# The mailbox_command parameter specifies the optional external
# command to use instead of mailbox delivery. The command is run as
# the recipient with proper HOME, SHELL and LOGNAME environment settings.
# Exception: delivery for root is done as $default_user.
#
# Other environment variables of interest: USER (recipient username),
# EXTENSION (address extension), DOMAIN (domain part of address),
# and LOCAL (the address localpart).
#
# Unlike other Postfix configuration parameters, the mailbox_command
# parameter is not subjected to $parameter substitutions. This is to
# make it easier to specify shell syntax (see example below).
#
# Avoid shell meta characters because they will force Postfix to run
# an expensive shell process. Procmail alone is expensive enough.
#
# IF YOU USE THIS TO DELIVER MAIL SYSTEM-WIDE, YOU MUST SET UP AN
# ALIAS THAT FORWARDS MAIL FOR ROOT TO A REAL USER.
#
#mailbox_command = /some/where/procmail
#mailbox_command = /some/where/procmail -a "$EXTENSION"

# The mailbox_transport specifies the optional transport in master.cf
# to use after processing aliases and .forward files. This parameter
# has precedence over the mailbox_command, fallback_transport and
# luser_relay parameters.
#
# Specify a string of the form transport:nexthop, where transport is
# the name of a mail delivery transport defined in master.cf. The
# :nexthop part is optional. For more details see the sample transport
# configuration file.
#
# NOTE: if you use this feature for accounts not in the UNIX password
# file, then you must update the "local_recipient_maps" setting in
# the main.cf file, otherwise the SMTP server will reject mail for
# non-UNIX accounts with "User unknown in local recipient table".
#
#mailbox_transport = lmtp:unix:/file/name
#mailbox_transport = cyrus

# The fallback_transport specifies the optional transport in master.cf
# to use for recipients that are not found in the UNIX passwd database.
# This parameter has precedence over the luser_relay parameter.
#
# Specify a string of the form transport:nexthop, where transport is
# the name of a mail delivery transport defined in master.cf. The
# :nexthop part is optional. For more details see the sample transport
# configuration file.
#
# NOTE: if you use this feature for accounts not in the UNIX password
# file, then you must update the "local_recipient_maps" setting in
# the main.cf file, otherwise the SMTP server will reject mail for
# non-UNIX accounts with "User unknown in local recipient table".
#
#fallback_transport = lmtp:unix:/file/name
#fallback_transport = cyrus
#fallback_transport =

# JUNK MAIL CONTROLS
#
# The controls listed here are only a very small subset. See the file
# sample-smtpd.cf for an elaborate list of anti-UCE controls.

# The header_checks parameter specifies an optional table with patterns
# that each logical message header is matched against, including
# headers that span multiple physical lines.
#
# By default, these patterns also apply to MIME headers and to the
# headers of attached messages. With older Postfix versions, MIME and
# attached message headers were treated as body text.
#
# For details, see the sample-filter.cf file.
#
#header_checks = regexp:/etc/postfix/header_checks

# FAST ETRN SERVICE
#
# Postfix maintains per-destination logfiles with information about
# deferred mail, so that mail can be flushed quickly with the SMTP
# "ETRN domain.tld" command, or by executing "sendmail -qRdomain.tld".
#
# By default, Postfix maintains deferred mail logfile information
# only for destinations that Postfix is willing to relay to (as
# specified in the relay_domains parameter). For other destinations,
# Postfix attempts to deliver ALL queued mail after receiving the
# SMTP "ETRN domain.tld" command, or after execution of "sendmail
# -qRdomain.tld". This can be slow when a lot of mail is queued.
#
# The fast_flush_domains parameter controls what destinations are
# eligible for this "fast ETRN/sendmail -qR" service.
#
#fast_flush_domains = $relay_domains
#fast_flush_domains =

# SHOW SOFTWARE VERSION OR NOT
#
# The smtpd_banner parameter specifies the text that follows the 220
# code in the SMTP server's greeting banner. Some people like to see
# the mail version advertised. By default, Postfix shows no version.
#
# You MUST specify $myhostname at the start of the text. That is an
# RFC requirement. Postfix itself does not care.
#
#smtpd_banner = $myhostname ESMTP $mail_name
#smtpd_banner = $myhostname ESMTP $mail_name ($mail_version)

# PARALLEL DELIVERY TO THE SAME DESTINATION
#
# How many parallel deliveries to the same user or domain? With local
# delivery, it does not make sense to do massively parallel delivery
# to the same user, because mailbox updates must happen sequentially,
# and expensive pipelines in .forward files can cause disasters when
# too many are run at the same time. With SMTP deliveries, 10
# simultaneous connections to the same domain could be sufficient to
# raise eyebrows.
#
# Each message delivery transport has its XXX_destination_concurrency_limit
# parameter. The default is $default_destination_concurrency_limit for
# most delivery transports. For the local delivery agent the default is 2.

# The debugger_command specifies the external command that is executed
# when a Postfix daemon program is run with the -D option.
#
# Use "command .. & sleep 5" so that the debugger can attach before
# the process marches on. If you use an X-based debugger, be sure to
# set up your XAUTHORITY environment variable before starting Postfix.
#
debugger_command =
PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
xxgdb $daemon_directory/$process_name $process_id & sleep 5

# INSTALL-TIME CONFIGURATION INFORMATION
#
# The following parameters are used when installing a new Postfix version.
#
# sendmail_path: The full pathname of the Postfix sendmail command.
# This is the Sendmail-compatible mail posting interface.
#
sendmail_path = /usr/sbin/sendmail.postfix

# newaliases_path: The full pathname of the Postfix newaliases command.
# This is the Sendmail-compatible command to build alias databases.
#
newaliases_path = /usr/bin/newaliases.postfix

# mailq_path: The full pathname of the Postfix mailq command. This
# is the Sendmail-compatible mail queue listing command.
#
mailq_path = /usr/bin/mailq.postfix

# setgid_group: The group for mail submission and queue management
# commands. This must be a group name with a numerical group ID that
# is not shared with other accounts, not even with the Postfix account.
#
setgid_group = postdrop